Loans and Card Member Receivables (Details 4) account in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) account	Mar. 31, 2020 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	46	27
Outstanding Balances \| $	$ 412	$ 269
Card Member Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	38	24
Outstanding Balances \| $	$ 287	$ 195
Average Interest Rate Reduction (as a percentage)	13.00%	14.00%
Card Member Receivables
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	7	3
Outstanding Balances \| $	$ 117	$ 74
Average Payment Term Extension (in months)	18 months	25 months
Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1
Outstanding Balances \| $	$ 8
Average Interest Rate Reduction (as a percentage)	3.00%
Average Payment Term Extension (in months)	15 months

The average basis point reduction in interest rate by class of Financial Instrument

No definition available.

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- Definition

The average period for payment term extension for cardmember receivables modified in a TDR.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

+ Details

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

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- Details

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- Details

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- Details

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